sys/bus/cam/scsi/scsi_target.c

   1 /*
   2  * Generic SCSI Target Kernel Mode Driver
   3  *
   4  * Copyright (c) 2002 Nate Lawson.
   5  * Copyright (c) 1998, 1999, 2001, 2002 Justin T. Gibbs.
   6  * All rights reserved.
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that the following conditions
  10  * are met:
  11  * 1. Redistributions of source code must retain the above copyright
  12  *    notice, this list of conditions, and the following disclaimer,
  13  *    without modification, immediately at the beginning of the file.
  14  * 2. The name of the author may not be used to endorse or promote products
  15  *    derived from this software without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
  21  * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  *
  29  * $FreeBSD: src/sys/cam/scsi/scsi_target.c,v 1.22.2.7 2003/02/18 22:07:10 njl Exp $
  30  * $DragonFly: src/sys/bus/cam/scsi/scsi_target.c,v 1.9 2004/05/19 22:52:38 dillon Exp $
  31  */
  32
  33 #include <sys/param.h>
  34 #include <sys/systm.h>
  35 #include <sys/kernel.h>
  36 #include <sys/conf.h>
  37 #include <sys/malloc.h>
  38 #include <sys/poll.h>
  39 #include <sys/vnode.h>
  40 #include <sys/devicestat.h>
  41
  42 #include "../cam.h"
  43 #include "../cam_ccb.h"
  44 #include "../cam_periph.h"
  45 #include "../cam_xpt_periph.h"
  46 #include "scsi_targetio.h"
  47
  48 /* Transaction information attached to each CCB sent by the user */
  49 struct targ_cmd_descr {
  50         struct cam_periph_map_info  mapinfo;
  51         TAILQ_ENTRY(targ_cmd_descr) tqe;
  52         union ccb *user_ccb;
  53         int        priority;
  54         int        func_code;
  55 };
  56
  57 /* Offset into the private CCB area for storing our descriptor */
  58 #define targ_descr      periph_priv.entries[1].ptr
  59
  60 TAILQ_HEAD(descr_queue, targ_cmd_descr);
  61
  62 typedef enum {
  63         TARG_STATE_RESV         = 0x00, /* Invalid state */
  64         TARG_STATE_OPENED       = 0x01, /* Device opened, softc initialized */
  65         TARG_STATE_LUN_ENABLED  = 0x02  /* Device enabled for a path */
  66 } targ_state;
  67
  68 /* Per-instance device software context */
  69 struct targ_softc {
  70         /* CCBs (CTIOs, ATIOs, INOTs) pending on the controller */
  71         struct ccb_queue         pending_ccb_queue;
  72
  73         /* Command descriptors awaiting CTIO resources from the XPT */
  74         struct descr_queue       work_queue;
  75
  76         /* Command descriptors that have been aborted back to the user. */
  77         struct descr_queue       abort_queue;
  78
  79         /*
  80          * Queue of CCBs that have been copied out to userland, but our
  81          * userland daemon has not yet seen.
  82          */
  83         struct ccb_queue         user_ccb_queue;
  84
  85         struct cam_periph       *periph;
  86         struct cam_path         *path;
  87         targ_state               state;
  88         struct selinfo           read_select;
  89         struct devstat           device_stats;
  90 };
  91
  92 static d_open_t         targopen;
  93 static d_close_t        targclose;
  94 static d_read_t         targread;
  95 static d_write_t        targwrite;
  96 static d_ioctl_t        targioctl;
  97 static d_poll_t         targpoll;
  98 static d_kqfilter_t     targkqfilter;
  99 static void             targreadfiltdetach(struct knote *kn);
 100 static int              targreadfilt(struct knote *kn, long hint);
 101 static struct filterops targread_filtops =
 102         { 1, NULL, targreadfiltdetach, targreadfilt };
 103
 104 #define TARG_CDEV_MAJOR 65
 105 static struct cdevsw targ_cdevsw = {
 106         /* name */      "targ",
 107         /* maj */       TARG_CDEV_MAJOR,
 108         /* flags */     D_KQFILTER,
 109         /* port */      NULL,
 110         /* clone */     NULL,
 111
 112         /* open */      targopen,
 113         /* close */     targclose,
 114         /* read */      targread,
 115         /* write */     targwrite,
 116         /* ioctl */     targioctl,
 117         /* poll */      targpoll,
 118         /* mmap */      nommap,
 119         /* strategy */  nostrategy,
 120         /* dump */      nodump,
 121         /* psize */     nopsize,
 122         /* kqfilter */  targkqfilter
 123 };
 124
 125 static cam_status       targendislun(struct cam_path *path, int enable,
 126                                      int grp6_len, int grp7_len);
 127 static cam_status       targenable(struct targ_softc *softc,
 128                                    struct cam_path *path,
 129                                    int grp6_len, int grp7_len);
 130 static cam_status       targdisable(struct targ_softc *softc);
 131 static periph_ctor_t    targctor;
 132 static periph_dtor_t    targdtor;
 133 static periph_start_t   targstart;
 134 static int              targusermerge(struct targ_softc *softc,
 135                                       struct targ_cmd_descr *descr,
 136                                       union ccb *ccb);
 137 static int              targsendccb(struct targ_softc *softc, union ccb *ccb,
 138                                     struct targ_cmd_descr *descr);
 139 static void             targdone(struct cam_periph *periph,
 140                                  union  ccb *done_ccb);
 141 static int              targreturnccb(struct targ_softc *softc,
 142                                       union  ccb *ccb);
 143 static union ccb *      targgetccb(struct targ_softc *softc, xpt_opcode type,
 144                                    int priority);
 145 static void             targfreeccb(struct targ_softc *softc, union ccb *ccb);
 146 static struct targ_cmd_descr *
 147                         targgetdescr(struct targ_softc *softc);
 148 static periph_init_t    targinit;
 149 static void             targasync(void *callback_arg, u_int32_t code,
 150                                   struct cam_path *path, void *arg);
 151 static void             abort_all_pending(struct targ_softc *softc);
 152 static void             notify_user(struct targ_softc *softc);
 153 static int              targcamstatus(cam_status status);
 154 static size_t           targccblen(xpt_opcode func_code);
 155
 156 static struct periph_driver targdriver =
 157 {
 158         targinit, "targ",
 159         TAILQ_HEAD_INITIALIZER(targdriver.units), /* generation */ 0
 160 };
 161 DATA_SET(periphdriver_set, targdriver);
 162
 163 static MALLOC_DEFINE(M_TARG, "TARG", "TARG data");
 164
 165 /* Create softc and initialize it. Only one proc can open each targ device. */
 166 static int
 167 targopen(dev_t dev, int flags, int fmt, struct proc *p)
 168 {
 169         struct targ_softc *softc;
 170
 171         if (dev->si_drv1 != 0) {
 172                 return (EBUSY);
 173         }
 174
 175         /* Mark device busy before any potentially blocking operations */
 176         dev->si_drv1 = (void *)~0;
 177         reference_dev(dev);             /* save ref for later destroy_dev() */
 178
 179         /* Create the targ device, allocate its softc, initialize it */
 180         make_dev(&targ_cdevsw, minor(dev), UID_ROOT, GID_WHEEL, 0600,
 181                          "targ%d", lminor(dev));
 182         MALLOC(softc, struct targ_softc *, sizeof(*softc), M_TARG,
 183                M_INTWAIT | M_ZERO);
 184         dev->si_drv1 = softc;
 185         softc->state = TARG_STATE_OPENED;
 186         softc->periph = NULL;
 187         softc->path = NULL;
 188
 189         TAILQ_INIT(&softc->pending_ccb_queue);
 190         TAILQ_INIT(&softc->work_queue);
 191         TAILQ_INIT(&softc->abort_queue);
 192         TAILQ_INIT(&softc->user_ccb_queue);
 193
 194         return (0);
 195 }
 196
 197 /* Disable LUN if enabled and teardown softc */
 198 static int
 199 targclose(dev_t dev, int flag, int fmt, struct proc *p)
 200 {
 201         struct targ_softc     *softc;
 202         int    error;
 203
 204         softc = (struct targ_softc *)dev->si_drv1;
 205         error = targdisable(softc);
 206         if (error == CAM_REQ_CMP) {
 207                 dev->si_drv1 = 0;
 208                 if (softc->periph != NULL) {
 209                         cam_periph_invalidate(softc->periph);
 210                         softc->periph = NULL;
 211                 }
 212                 destroy_dev(dev);       /* eats the open ref */
 213                 FREE(softc, M_TARG);
 214         } else {
 215                 release_dev(dev);
 216         }
 217         return (error);
 218 }
 219
 220 /* Enable/disable LUNs, set debugging level */
 221 static int
 222 targioctl(dev_t dev, u_long cmd, caddr_t addr, int flag, struct proc *p)
 223 {
 224         struct targ_softc *softc;
 225         cam_status         status;
 226
 227         softc = (struct targ_softc *)dev->si_drv1;
 228
 229         switch (cmd) {
 230         case TARGIOCENABLE:
 231         {
 232                 struct ioc_enable_lun   *new_lun;
 233                 struct cam_path         *path;
 234
 235                 new_lun = (struct ioc_enable_lun *)addr;
 236                 status = xpt_create_path(&path, /*periph*/NULL,
 237                                          new_lun->path_id,
 238                                          new_lun->target_id,
 239                                          new_lun->lun_id);
 240                 if (status != CAM_REQ_CMP) {
 241                         printf("Couldn't create path, status %#x\n", status);
 242                         break;
 243                 }
 244                 status = targenable(softc, path, new_lun->grp6_len,
 245                                     new_lun->grp7_len);
 246                 xpt_free_path(path);
 247                 break;
 248         }
 249         case TARGIOCDISABLE:
 250                 status = targdisable(softc);
 251                 break;
 252         case TARGIOCDEBUG:
 253         {
 254 #ifdef  CAMDEBUG
 255                 struct ccb_debug cdbg;
 256
 257                 bzero(&cdbg, sizeof cdbg);
 258                 if (*((int *)addr) != 0)
 259                         cdbg.flags = CAM_DEBUG_PERIPH;
 260                 else
 261                         cdbg.flags = CAM_DEBUG_NONE;
 262                 xpt_setup_ccb(&cdbg.ccb_h, softc->path, /*priority*/0);
 263                 cdbg.ccb_h.func_code = XPT_DEBUG;
 264                 cdbg.ccb_h.cbfcnp = targdone;
 265
 266                 /* If no periph available, disallow debugging changes */
 267                 if ((softc->state & TARG_STATE_LUN_ENABLED) == 0) {
 268                         status = CAM_DEV_NOT_THERE;
 269                         break;
 270                 }
 271                 xpt_action((union ccb *)&cdbg);
 272                 status = cdbg.ccb_h.status & CAM_STATUS_MASK;
 273 #else
 274                 status = CAM_FUNC_NOTAVAIL;
 275 #endif
 276                 break;
 277         }
 278         default:
 279                 status = CAM_PROVIDE_FAIL;
 280                 break;
 281         }
 282
 283         return (targcamstatus(status));
 284 }
 285
 286 /* Writes are always ready, reads wait for user_ccb_queue or abort_queue */
 287 static int
 288 targpoll(dev_t dev, int poll_events, struct proc *p)
 289 {
 290         struct targ_softc *softc;
 291         int     revents, s;
 292
 293         softc = (struct targ_softc *)dev->si_drv1;
 294
 295         /* Poll for write() is always ok. */
 296         revents = poll_events & (POLLOUT | POLLWRNORM);
 297         if ((poll_events & (POLLIN | POLLRDNORM)) != 0) {
 298                 s = splsoftcam();
 299                 /* Poll for read() depends on user and abort queues. */
 300                 if (!TAILQ_EMPTY(&softc->user_ccb_queue) ||
 301                     !TAILQ_EMPTY(&softc->abort_queue)) {
 302                         revents |= poll_events & (POLLIN | POLLRDNORM);
 303                 }
 304                 /* Only sleep if the user didn't poll for write. */
 305                 if (revents == 0)
 306                         selrecord(p, &softc->read_select);
 307                 splx(s);
 308         }
 309
 310         return (revents);
 311 }
 312
 313 static int
 314 targkqfilter(dev_t dev, struct knote *kn)
 315 {
 316         struct  targ_softc *softc;
 317         int     s;
 318
 319         softc = (struct targ_softc *)dev->si_drv1;
 320         kn->kn_hook = (caddr_t)softc;
 321         kn->kn_fop = &targread_filtops;
 322         s = splsoftcam();
 323         SLIST_INSERT_HEAD(&softc->read_select.si_note, kn, kn_selnext);
 324         splx(s);
 325         return (0);
 326 }
 327
 328 static void
 329 targreadfiltdetach(struct knote *kn)
 330 {
 331         struct  targ_softc *softc;
 332         int     s;
 333
 334         softc = (struct targ_softc *)kn->kn_hook;
 335         s = splsoftcam();
 336         SLIST_REMOVE(&softc->read_select.si_note, kn, knote, kn_selnext);
 337         splx(s);
 338 }
 339
 340 /* Notify the user's kqueue when the user queue or abort queue gets a CCB */
 341 static int
 342 targreadfilt(struct knote *kn, long hint)
 343 {
 344         struct targ_softc *softc;
 345         int     retval, s;
 346
 347         softc = (struct targ_softc *)kn->kn_hook;
 348         s = splsoftcam();
 349         retval = !TAILQ_EMPTY(&softc->user_ccb_queue) ||
 350                  !TAILQ_EMPTY(&softc->abort_queue);
 351         splx(s);
 352         return (retval);
 353 }
 354
 355 /* Send the HBA the enable/disable message */
 356 static cam_status
 357 targendislun(struct cam_path *path, int enable, int grp6_len, int grp7_len)
 358 {
 359         struct ccb_en_lun en_ccb;
 360         cam_status        status;
 361
 362         /* Tell the lun to begin answering selects */
 363         xpt_setup_ccb(&en_ccb.ccb_h, path, /*priority*/1);
 364         en_ccb.ccb_h.func_code = XPT_EN_LUN;
 365         /* Don't need support for any vendor specific commands */
 366         en_ccb.grp6_len = grp6_len;
 367         en_ccb.grp7_len = grp7_len;
 368         en_ccb.enable = enable ? 1 : 0;
 369         xpt_action((union ccb *)&en_ccb);
 370         status = en_ccb.ccb_h.status & CAM_STATUS_MASK;
 371         if (status != CAM_REQ_CMP) {
 372                 xpt_print_path(path);
 373                 printf("%sable lun CCB rejected, status %#x\n",
 374                        enable ? "en" : "dis", status);
 375         }
 376         return (status);
 377 }
 378
 379 /* Enable target mode on a LUN, given its path */
 380 static cam_status
 381 targenable(struct targ_softc *softc, struct cam_path *path, int grp6_len,
 382            int grp7_len)
 383 {
 384         struct cam_periph *periph;
 385         struct ccb_pathinq cpi;
 386         cam_status         status;
 387
 388         if ((softc->state & TARG_STATE_LUN_ENABLED) != 0)
 389                 return (CAM_LUN_ALRDY_ENA);
 390
 391         /* Make sure SIM supports target mode */
 392         xpt_setup_ccb(&cpi.ccb_h, path, /*priority*/1);
 393         cpi.ccb_h.func_code = XPT_PATH_INQ;
 394         xpt_action((union ccb *)&cpi);
 395         status = cpi.ccb_h.status & CAM_STATUS_MASK;
 396         if (status != CAM_REQ_CMP) {
 397                 printf("pathinq failed, status %#x\n", status);
 398                 goto enable_fail;
 399         }
 400         if ((cpi.target_sprt & PIT_PROCESSOR) == 0) {
 401                 printf("controller does not support target mode\n");
 402                 status = CAM_FUNC_NOTAVAIL;
 403                 goto enable_fail;
 404         }
 405
 406         /* Destroy any periph on our path if it is disabled */
 407         periph = cam_periph_find(path, "targ");
 408         if (periph != NULL) {
 409                 struct targ_softc *del_softc;
 410
 411                 del_softc = (struct targ_softc *)periph->softc;
 412                 if ((del_softc->state & TARG_STATE_LUN_ENABLED) == 0) {
 413                         cam_periph_invalidate(del_softc->periph);
 414                         del_softc->periph = NULL;
 415                 } else {
 416                         printf("Requested path still in use by targ%d\n",
 417                                periph->unit_number);
 418                         status = CAM_LUN_ALRDY_ENA;
 419                         goto enable_fail;
 420                 }
 421         }
 422
 423         /* Create a periph instance attached to this path */
 424         status = cam_periph_alloc(targctor, NULL, targdtor, targstart,
 425                         "targ", CAM_PERIPH_BIO, path, targasync, 0, softc);
 426         if (status != CAM_REQ_CMP) {
 427                 printf("cam_periph_alloc failed, status %#x\n", status);
 428                 goto enable_fail;
 429         }
 430
 431         /* Ensure that the periph now exists. */
 432         if (cam_periph_find(path, "targ") == NULL) {
 433                 panic("targenable: succeeded but no periph?");
 434                 /* NOTREACHED */
 435         }
 436
 437         /* Send the enable lun message */
 438         status = targendislun(path, /*enable*/1, grp6_len, grp7_len);
 439         if (status != CAM_REQ_CMP) {
 440                 printf("enable lun failed, status %#x\n", status);
 441                 goto enable_fail;
 442         }
 443         softc->state |= TARG_STATE_LUN_ENABLED;
 444
 445 enable_fail:
 446         return (status);
 447 }
 448
 449 /* Disable this softc's target instance if enabled */
 450 static cam_status
 451 targdisable(struct targ_softc *softc)
 452 {
 453         cam_status status;
 454         int s;
 455
 456         if ((softc->state & TARG_STATE_LUN_ENABLED) == 0)
 457                 return (CAM_REQ_CMP);
 458
 459         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("targdisable\n"));
 460
 461         /* Abort any ccbs pending on the controller */
 462         s = splcam();
 463         abort_all_pending(softc);
 464         splx(s);
 465
 466         /* Disable this lun */
 467         status = targendislun(softc->path, /*enable*/0,
 468                               /*grp6_len*/0, /*grp7_len*/0);
 469         if (status == CAM_REQ_CMP)
 470                 softc->state &= ~TARG_STATE_LUN_ENABLED;
 471         else
 472                 printf("Disable lun failed, status %#x\n", status);
 473
 474         return (status);
 475 }
 476
 477 /* Initialize a periph (called from cam_periph_alloc) */
 478 static cam_status
 479 targctor(struct cam_periph *periph, void *arg)
 480 {
 481         struct targ_softc *softc;
 482
 483         /* Store pointer to softc for periph-driven routines */
 484         softc = (struct targ_softc *)arg;
 485         periph->softc = softc;
 486         softc->periph = periph;
 487         softc->path = periph->path;
 488         return (CAM_REQ_CMP);
 489 }
 490
 491 static void
 492 targdtor(struct cam_periph *periph)
 493 {
 494         struct targ_softc     *softc;
 495         struct ccb_hdr        *ccb_h;
 496         struct targ_cmd_descr *descr;
 497
 498         softc = (struct targ_softc *)periph->softc;
 499
 500         /*
 501          * targdisable() aborts CCBs back to the user and leaves them
 502          * on user_ccb_queue and abort_queue in case the user is still
 503          * interested in them.  We free them now.
 504          */
 505         while ((ccb_h = TAILQ_FIRST(&softc->user_ccb_queue)) != NULL) {
 506                 TAILQ_REMOVE(&softc->user_ccb_queue, ccb_h, periph_links.tqe);
 507                 targfreeccb(softc, (union ccb *)ccb_h);
 508         }
 509         while ((descr = TAILQ_FIRST(&softc->abort_queue)) != NULL) {
 510                 TAILQ_REMOVE(&softc->abort_queue, descr, tqe);
 511                 FREE(descr, M_TARG);
 512         }
 513
 514         softc->periph = NULL;
 515         softc->path = NULL;
 516         periph->softc = NULL;
 517 }
 518
 519 /* Receive CCBs from user mode proc and send them to the HBA */
 520 static int
 521 targwrite(dev_t dev, struct uio *uio, int ioflag)
 522 {
 523         union ccb *user_ccb;
 524         struct targ_softc *softc;
 525         struct targ_cmd_descr *descr;
 526         int write_len, error, s;
 527         int func_code, priority;
 528
 529         softc = (struct targ_softc *)dev->si_drv1;
 530         write_len = error = 0;
 531         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
 532                   ("write - uio_resid %d\n", uio->uio_resid));
 533         while (uio->uio_resid >= sizeof(user_ccb) && error == 0) {
 534                 union ccb *ccb;
 535                 int error;
 536
 537                 error = uiomove((caddr_t)&user_ccb, sizeof(user_ccb), uio);
 538                 if (error != 0) {
 539                         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
 540                                   ("write - uiomove failed (%d)\n", error));
 541                         break;
 542                 }
 543                 priority = fuword(&user_ccb->ccb_h.pinfo.priority);
 544                 if (priority == -1) {
 545                         error = EINVAL;
 546                         break;
 547                 }
 548                 func_code = fuword(&user_ccb->ccb_h.func_code);
 549                 switch (func_code) {
 550                 case XPT_ACCEPT_TARGET_IO:
 551                 case XPT_IMMED_NOTIFY:
 552                         ccb = targgetccb(softc, func_code, priority);
 553                         descr = (struct targ_cmd_descr *)ccb->ccb_h.targ_descr;
 554                         descr->user_ccb = user_ccb;
 555                         descr->func_code = func_code;
 556                         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
 557                                   ("Sent ATIO/INOT (%p)\n", user_ccb));
 558                         xpt_action(ccb);
 559                         s = splsoftcam();
 560                         TAILQ_INSERT_TAIL(&softc->pending_ccb_queue,
 561                                           &ccb->ccb_h,
 562                                           periph_links.tqe);
 563                         splx(s);
 564                         break;
 565                 default:
 566                         if ((func_code & XPT_FC_QUEUED) != 0) {
 567                                 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
 568                                           ("Sending queued ccb %#x (%p)\n",
 569                                           func_code, user_ccb));
 570                                 descr = targgetdescr(softc);
 571                                 descr->user_ccb = user_ccb;
 572                                 descr->priority = priority;
 573                                 descr->func_code = func_code;
 574                                 s = splsoftcam();
 575                                 TAILQ_INSERT_TAIL(&softc->work_queue,
 576                                                   descr, tqe);
 577                                 splx(s);
 578                                 xpt_schedule(softc->periph, priority);
 579                         } else {
 580                                 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
 581                                           ("Sending inline ccb %#x (%p)\n",
 582                                           func_code, user_ccb));
 583                                 ccb = targgetccb(softc, func_code, priority);
 584                                 descr = (struct targ_cmd_descr *)
 585                                          ccb->ccb_h.targ_descr;
 586                                 descr->user_ccb = user_ccb;
 587                                 descr->priority = priority;
 588                                 descr->func_code = func_code;
 589                                 if (targusermerge(softc, descr, ccb) != EFAULT)
 590                                         targsendccb(softc, ccb, descr);
 591                                 targreturnccb(softc, ccb);
 592                         }
 593                         break;
 594                 }
 595                 write_len += sizeof(user_ccb);
 596         }
 597
 598         /*
 599          * If we've successfully taken in some amount of
 600          * data, return success for that data first.  If
 601          * an error is persistent, it will be reported
 602          * on the next write.
 603          */
 604         if (error != 0 && write_len == 0)
 605                 return (error);
 606         if (write_len == 0 && uio->uio_resid != 0)
 607                 return (ENOSPC);
 608         return (0);
 609 }
 610
 611 /* Process requests (descrs) via the periph-supplied CCBs */
 612 static void
 613 targstart(struct cam_periph *periph, union ccb *start_ccb)
 614 {
 615         struct targ_softc *softc;
 616         struct targ_cmd_descr *descr, *next_descr;
 617         int s, error;
 618
 619         softc = (struct targ_softc *)periph->softc;
 620         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("targstart %p\n", start_ccb));
 621
 622         s = splsoftcam();
 623         descr = TAILQ_FIRST(&softc->work_queue);
 624         if (descr == NULL) {
 625                 splx(s);
 626                 xpt_release_ccb(start_ccb);
 627         } else {
 628                 TAILQ_REMOVE(&softc->work_queue, descr, tqe);
 629                 next_descr = TAILQ_FIRST(&softc->work_queue);
 630                 splx(s);
 631
 632                 /* Initiate a transaction using the descr and supplied CCB */
 633                 error = targusermerge(softc, descr, start_ccb);
 634                 if (error == 0)
 635                         error = targsendccb(softc, start_ccb, descr);
 636                 if (error != 0) {
 637                         xpt_print_path(periph->path);
 638                         printf("targsendccb failed, err %d\n", error);
 639                         xpt_release_ccb(start_ccb);
 640                         suword(&descr->user_ccb->ccb_h.status,
 641                                CAM_REQ_CMP_ERR);
 642                         s = splsoftcam();
 643                         TAILQ_INSERT_TAIL(&softc->abort_queue, descr, tqe);
 644                         splx(s);
 645                         notify_user(softc);
 646                 }
 647
 648                 /* If we have more work to do, stay scheduled */
 649                 if (next_descr != NULL)
 650                         xpt_schedule(periph, next_descr->priority);
 651         }
 652 }
 653
 654 static int
 655 targusermerge(struct targ_softc *softc, struct targ_cmd_descr *descr,
 656               union ccb *ccb)
 657 {
 658         struct ccb_hdr *u_ccbh, *k_ccbh;
 659         size_t ccb_len;
 660         int error;
 661
 662         u_ccbh = &descr->user_ccb->ccb_h;
 663         k_ccbh = &ccb->ccb_h;
 664
 665         /*
 666          * There are some fields in the CCB header that need to be
 667          * preserved, the rest we get from the user ccb. (See xpt_merge_ccb)
 668          */
 669         xpt_setup_ccb(k_ccbh, softc->path, descr->priority);
 670         k_ccbh->retry_count = fuword(&u_ccbh->retry_count);
 671         k_ccbh->func_code = descr->func_code;
 672         k_ccbh->flags = fuword(&u_ccbh->flags);
 673         k_ccbh->timeout = fuword(&u_ccbh->timeout);
 674         ccb_len = targccblen(k_ccbh->func_code) - sizeof(struct ccb_hdr);
 675         error = copyin(u_ccbh + 1, k_ccbh + 1, ccb_len);
 676         if (error != 0) {
 677                 k_ccbh->status = CAM_REQ_CMP_ERR;
 678                 return (error);
 679         }
 680
 681         /* Translate usermode abort_ccb pointer to its kernel counterpart */
 682         if (k_ccbh->func_code == XPT_ABORT) {
 683                 struct ccb_abort *cab;
 684                 struct ccb_hdr *ccb_h;
 685                 int s;
 686
 687                 cab = (struct ccb_abort *)ccb;
 688                 s = splsoftcam();
 689                 TAILQ_FOREACH(ccb_h, &softc->pending_ccb_queue,
 690                     periph_links.tqe) {
 691                         struct targ_cmd_descr *ab_descr;
 692
 693                         ab_descr = (struct targ_cmd_descr *)ccb_h->targ_descr;
 694                         if (ab_descr->user_ccb == cab->abort_ccb) {
 695                                 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
 696                                           ("Changing abort for %p to %p\n",
 697                                           cab->abort_ccb, ccb_h));
 698                                 cab->abort_ccb = (union ccb *)ccb_h;
 699                                 break;
 700                         }
 701                 }
 702                 splx(s);
 703                 /* CCB not found, set appropriate status */
 704                 if (ccb_h == NULL) {
 705                         k_ccbh->status = CAM_PATH_INVALID;
 706                         error = ESRCH;
 707                 }
 708         }
 709
 710         return (error);
 711 }
 712
 713 /* Build and send a kernel CCB formed from descr->user_ccb */
 714 static int
 715 targsendccb(struct targ_softc *softc, union ccb *ccb,
 716             struct targ_cmd_descr *descr)
 717 {
 718         struct cam_periph_map_info *mapinfo;
 719         struct ccb_hdr *ccb_h;
 720         int error;
 721
 722         ccb_h = &ccb->ccb_h;
 723         mapinfo = &descr->mapinfo;
 724         mapinfo->num_bufs_used = 0;
 725
 726         /*
 727          * There's no way for the user to have a completion
 728          * function, so we put our own completion function in here.
 729          * We also stash in a reference to our descriptor so targreturnccb()
 730          * can find our mapping info.
 731          */
 732         ccb_h->cbfcnp = targdone;
 733         ccb_h->targ_descr = descr;
 734
 735         /*
 736          * We only attempt to map the user memory into kernel space
 737          * if they haven't passed in a physical memory pointer,
 738          * and if there is actually an I/O operation to perform.
 739          * Right now cam_periph_mapmem() only supports SCSI and device
 740          * match CCBs.  For the SCSI CCBs, we only pass the CCB in if
 741          * there's actually data to map.  cam_periph_mapmem() will do the
 742          * right thing, even if there isn't data to map, but since CCBs
 743          * without data are a reasonably common occurance (e.g. test unit
 744          * ready), it will save a few cycles if we check for it here.
 745          */
 746         if (((ccb_h->flags & CAM_DATA_PHYS) == 0)
 747          && (((ccb_h->func_code == XPT_CONT_TARGET_IO)
 748             && ((ccb_h->flags & CAM_DIR_MASK) != CAM_DIR_NONE))
 749           || (ccb_h->func_code == XPT_DEV_MATCH))) {
 750
 751                 error = cam_periph_mapmem(ccb, mapinfo);
 752
 753                 /*
 754                  * cam_periph_mapmem returned an error, we can't continue.
 755                  * Return the error to the user.
 756                  */
 757                 if (error) {
 758                         ccb_h->status = CAM_REQ_CMP_ERR;
 759                         mapinfo->num_bufs_used = 0;
 760                         return (error);
 761                 }
 762         }
 763
 764         /*
 765          * Once queued on the pending CCB list, this CCB will be protected
 766          * by our error recovery handler.
 767          */
 768         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("sendccb %p\n", ccb));
 769         if (XPT_FC_IS_QUEUED(ccb)) {
 770                 int s;
 771
 772                 s = splsoftcam();
 773                 TAILQ_INSERT_TAIL(&softc->pending_ccb_queue, ccb_h,
 774                                   periph_links.tqe);
 775                 splx(s);
 776         }
 777         xpt_action(ccb);
 778
 779         return (0);
 780 }
 781
 782 /* Completion routine for CCBs (called at splsoftcam) */
 783 static void
 784 targdone(struct cam_periph *periph, union ccb *done_ccb)
 785 {
 786         struct targ_softc *softc;
 787         cam_status status;
 788
 789         CAM_DEBUG(periph->path, CAM_DEBUG_PERIPH, ("targdone %p\n", done_ccb));
 790         softc = (struct targ_softc *)periph->softc;
 791         TAILQ_REMOVE(&softc->pending_ccb_queue, &done_ccb->ccb_h,
 792                      periph_links.tqe);
 793         status = done_ccb->ccb_h.status & CAM_STATUS_MASK;
 794
 795         /* If we're no longer enabled, throw away CCB */
 796         if ((softc->state & TARG_STATE_LUN_ENABLED) == 0) {
 797                 targfreeccb(softc, done_ccb);
 798                 return;
 799         }
 800         /* abort_all_pending() waits for pending queue to be empty */
 801         if (TAILQ_EMPTY(&softc->pending_ccb_queue))
 802                 wakeup(&softc->pending_ccb_queue);
 803
 804         switch (done_ccb->ccb_h.func_code) {
 805         /* All FC_*_QUEUED CCBs go back to userland */
 806         case XPT_IMMED_NOTIFY:
 807         case XPT_ACCEPT_TARGET_IO:
 808         case XPT_CONT_TARGET_IO:
 809                 TAILQ_INSERT_TAIL(&softc->user_ccb_queue, &done_ccb->ccb_h,
 810                                   periph_links.tqe);
 811                 notify_user(softc);
 812                 break;
 813         default:
 814                 panic("targdone: impossible xpt opcode %#x",
 815                       done_ccb->ccb_h.func_code);
 816                 /* NOTREACHED */
 817         }
 818 }
 819
 820 /* Return CCBs to the user from the user queue and abort queue */
 821 static int
 822 targread(dev_t dev, struct uio *uio, int ioflag)
 823 {
 824         struct descr_queue      *abort_queue;
 825         struct targ_cmd_descr   *user_descr;
 826         struct targ_softc       *softc;
 827         struct ccb_queue  *user_queue;
 828         struct ccb_hdr    *ccb_h;
 829         union  ccb        *user_ccb;
 830         int                read_len, error, s;
 831
 832         error = 0;
 833         read_len = 0;
 834         softc = (struct targ_softc *)dev->si_drv1;
 835         user_queue = &softc->user_ccb_queue;
 836         abort_queue = &softc->abort_queue;
 837         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("targread\n"));
 838
 839         /* If no data is available, wait or return immediately */
 840         s = splsoftcam();
 841         ccb_h = TAILQ_FIRST(user_queue);
 842         user_descr = TAILQ_FIRST(abort_queue);
 843         while (ccb_h == NULL && user_descr == NULL) {
 844                 if ((ioflag & IO_NDELAY) == 0) {
 845                         error = tsleep(user_queue, PCATCH, "targrd", 0);
 846                         ccb_h = TAILQ_FIRST(user_queue);
 847                         user_descr = TAILQ_FIRST(abort_queue);
 848                         if (error != 0) {
 849                                 if (error == ERESTART) {
 850                                         continue;
 851                                 } else {
 852                                         splx(s);
 853                                         goto read_fail;
 854                                 }
 855                         }
 856                 } else {
 857                         splx(s);
 858                         return (EAGAIN);
 859                 }
 860         }
 861
 862         /* Data is available so fill the user's buffer */
 863         while (ccb_h != NULL) {
 864                 struct targ_cmd_descr *descr;
 865
 866                 if (uio->uio_resid < sizeof(user_ccb))
 867                         break;
 868                 TAILQ_REMOVE(user_queue, ccb_h, periph_links.tqe);
 869                 splx(s);
 870                 descr = (struct targ_cmd_descr *)ccb_h->targ_descr;
 871                 user_ccb = descr->user_ccb;
 872                 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
 873                           ("targread ccb %p (%p)\n", ccb_h, user_ccb));
 874                 error = targreturnccb(softc, (union ccb *)ccb_h);
 875                 if (error != 0)
 876                         goto read_fail;
 877                 error = uiomove((caddr_t)&user_ccb, sizeof(user_ccb), uio);
 878                 if (error != 0)
 879                         goto read_fail;
 880                 read_len += sizeof(user_ccb);
 881
 882                 s = splsoftcam();
 883                 ccb_h = TAILQ_FIRST(user_queue);
 884         }
 885
 886         /* Flush out any aborted descriptors */
 887         while (user_descr != NULL) {
 888                 if (uio->uio_resid < sizeof(user_ccb))
 889                         break;
 890                 TAILQ_REMOVE(abort_queue, user_descr, tqe);
 891                 splx(s);
 892                 user_ccb = user_descr->user_ccb;
 893                 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
 894                           ("targread aborted descr %p (%p)\n",
 895                           user_descr, user_ccb));
 896                 suword(&user_ccb->ccb_h.status, CAM_REQ_ABORTED);
 897                 error = uiomove((caddr_t)&user_ccb, sizeof(user_ccb), uio);
 898                 if (error != 0)
 899                         goto read_fail;
 900                 read_len += sizeof(user_ccb);
 901
 902                 s = splsoftcam();
 903                 user_descr = TAILQ_FIRST(abort_queue);
 904         }
 905         splx(s);
 906
 907         /*
 908          * If we've successfully read some amount of data, don't report an
 909          * error.  If the error is persistent, it will be reported on the
 910          * next read().
 911          */
 912         if (read_len == 0 && uio->uio_resid != 0)
 913                 error = ENOSPC;
 914
 915 read_fail:
 916         return (error);
 917 }
 918
 919 /* Copy completed ccb back to the user */
 920 static int
 921 targreturnccb(struct targ_softc *softc, union ccb *ccb)
 922 {
 923         struct targ_cmd_descr *descr;
 924         struct ccb_hdr *u_ccbh;
 925         size_t ccb_len;
 926         int error;
 927
 928         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("targreturnccb %p\n", ccb));
 929         descr = (struct targ_cmd_descr *)ccb->ccb_h.targ_descr;
 930         u_ccbh = &descr->user_ccb->ccb_h;
 931
 932         /* Copy out the central portion of the ccb_hdr */
 933         copyout(&ccb->ccb_h.retry_count, &u_ccbh->retry_count,
 934                 offsetof(struct ccb_hdr, periph_priv) -
 935                 offsetof(struct ccb_hdr, retry_count));
 936
 937         /* Copy out the rest of the ccb (after the ccb_hdr) */
 938         ccb_len = targccblen(ccb->ccb_h.func_code) - sizeof(struct ccb_hdr);
 939         if (descr->mapinfo.num_bufs_used != 0)
 940                 cam_periph_unmapmem(ccb, &descr->mapinfo);
 941         error = copyout(&ccb->ccb_h + 1, u_ccbh + 1, ccb_len);
 942         if (error != 0) {
 943                 xpt_print_path(softc->path);
 944                 printf("targreturnccb - CCB copyout failed (%d)\n",
 945                        error);
 946         }
 947         /* Free CCB or send back to devq. */
 948         targfreeccb(softc, ccb);
 949
 950         return (error);
 951 }
 952
 953 static union ccb *
 954 targgetccb(struct targ_softc *softc, xpt_opcode type, int priority)
 955 {
 956         union ccb *ccb;
 957         int ccb_len;
 958
 959         ccb_len = targccblen(type);
 960         MALLOC(ccb, union ccb *, ccb_len, M_TARG, M_INTWAIT);
 961         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("getccb %p\n", ccb));
 962
 963         xpt_setup_ccb(&ccb->ccb_h, softc->path, priority);
 964         ccb->ccb_h.func_code = type;
 965         ccb->ccb_h.cbfcnp = targdone;
 966         ccb->ccb_h.targ_descr = targgetdescr(softc);
 967         return (ccb);
 968 }
 969
 970 static void
 971 targfreeccb(struct targ_softc *softc, union ccb *ccb)
 972 {
 973         CAM_DEBUG_PRINT(CAM_DEBUG_PERIPH, ("targfreeccb descr %p and\n",
 974                         ccb->ccb_h.targ_descr));
 975         FREE(ccb->ccb_h.targ_descr, M_TARG);
 976
 977         switch (ccb->ccb_h.func_code) {
 978         case XPT_ACCEPT_TARGET_IO:
 979         case XPT_IMMED_NOTIFY:
 980                 CAM_DEBUG_PRINT(CAM_DEBUG_PERIPH, ("freeing ccb %p\n", ccb));
 981                 FREE(ccb, M_TARG);
 982                 break;
 983         default:
 984                 /* Send back CCB if we got it from the periph */
 985                 if (XPT_FC_IS_QUEUED(ccb)) {
 986                         CAM_DEBUG_PRINT(CAM_DEBUG_PERIPH,
 987                                         ("returning queued ccb %p\n", ccb));
 988                         xpt_release_ccb(ccb);
 989                 } else {
 990                         CAM_DEBUG_PRINT(CAM_DEBUG_PERIPH,
 991                                         ("freeing ccb %p\n", ccb));
 992                         FREE(ccb, M_TARG);
 993                 }
 994                 break;
 995         }
 996 }
 997
 998 static struct targ_cmd_descr *
 999 targgetdescr(struct targ_softc *softc)
1000 {
1001         struct targ_cmd_descr *descr;
1002
1003         MALLOC(descr, struct targ_cmd_descr *, sizeof(*descr),
1004                 M_TARG, M_INTWAIT);
1005         descr->mapinfo.num_bufs_used = 0;
1006         return (descr);
1007 }
1008
1009 static void
1010 targinit(void)
1011 {
1012         cdevsw_add(&targ_cdevsw, 0, 0);
1013 }
1014
1015 static void
1016 targasync(void *callback_arg, u_int32_t code, struct cam_path *path, void *arg)
1017 {
1018         /* All events are handled in usermode by INOTs */
1019         panic("targasync() called, should be an INOT instead");
1020 }
1021
1022 /* Cancel all pending requests and CCBs awaiting work. */
1023 static void
1024 abort_all_pending(struct targ_softc *softc)
1025 {
1026         struct targ_cmd_descr   *descr;
1027         struct ccb_abort         cab;
1028         struct ccb_hdr          *ccb_h;
1029
1030         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("abort_all_pending\n"));
1031
1032         /* First abort the descriptors awaiting resources */
1033         while ((descr = TAILQ_FIRST(&softc->work_queue)) != NULL) {
1034                 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
1035                           ("Aborting descr from workq %p\n", descr));
1036                 TAILQ_REMOVE(&softc->work_queue, descr, tqe);
1037                 TAILQ_INSERT_TAIL(&softc->abort_queue, descr, tqe);
1038         }
1039
1040         /*
1041          * Then abort all pending CCBs.
1042          * targdone() will return the aborted CCB via user_ccb_queue
1043          */
1044         xpt_setup_ccb(&cab.ccb_h, softc->path, /*priority*/0);
1045         cab.ccb_h.func_code = XPT_ABORT;
1046         cab.ccb_h.status = CAM_REQ_CMP_ERR;
1047         TAILQ_FOREACH(ccb_h, &softc->pending_ccb_queue, periph_links.tqe) {
1048                 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
1049                           ("Aborting pending CCB %p\n", ccb_h));
1050                 cab.abort_ccb = (union ccb *)ccb_h;
1051                 xpt_action((union ccb *)&cab);
1052                 if (cab.ccb_h.status != CAM_REQ_CMP) {
1053                         xpt_print_path(cab.ccb_h.path);
1054                         printf("Unable to abort CCB, status %#x\n",
1055                                cab.ccb_h.status);
1056                 }
1057         }
1058
1059         /* If we aborted at least one pending CCB ok, wait for it. */
1060         if (cab.ccb_h.status == CAM_REQ_CMP) {
1061                 tsleep(&softc->pending_ccb_queue, PCATCH, "tgabrt", 0);
1062         }
1063
1064         /* If we aborted anything from the work queue, wakeup user. */
1065         if (!TAILQ_EMPTY(&softc->user_ccb_queue)
1066          || !TAILQ_EMPTY(&softc->abort_queue))
1067                 notify_user(softc);
1068 }
1069
1070 /* Notify the user that data is ready */
1071 static void
1072 notify_user(struct targ_softc *softc)
1073 {
1074         /*
1075          * Notify users sleeping via poll(), kqueue(), and
1076          * blocking read().
1077          */
1078         selwakeup(&softc->read_select);
1079         KNOTE(&softc->read_select.si_note, 0);
1080         wakeup(&softc->user_ccb_queue);
1081 }
1082
1083 /* Convert CAM status to errno values */
1084 static int
1085 targcamstatus(cam_status status)
1086 {
1087         switch (status & CAM_STATUS_MASK) {
1088         case CAM_REQ_CMP:       /* CCB request completed without error */
1089                 return (0);
1090         case CAM_REQ_INPROG:    /* CCB request is in progress */
1091                 return (EINPROGRESS);
1092         case CAM_REQ_CMP_ERR:   /* CCB request completed with an error */
1093                 return (EIO);
1094         case CAM_PROVIDE_FAIL:  /* Unable to provide requested capability */
1095                 return (ENOTTY);
1096         case CAM_FUNC_NOTAVAIL: /* The requested function is not available */
1097                 return (ENOTSUP);
1098         case CAM_LUN_ALRDY_ENA: /* LUN is already enabled for target mode */
1099                 return (EADDRINUSE);
1100         case CAM_PATH_INVALID:  /* Supplied Path ID is invalid */
1101         case CAM_DEV_NOT_THERE: /* SCSI Device Not Installed/there */
1102                 return (ENOENT);
1103         case CAM_REQ_ABORTED:   /* CCB request aborted by the host */
1104                 return (ECANCELED);
1105         case CAM_CMD_TIMEOUT:   /* Command timeout */
1106                 return (ETIMEDOUT);
1107         case CAM_REQUEUE_REQ:   /* Requeue to preserve transaction ordering */
1108                 return (EAGAIN);
1109         case CAM_REQ_INVALID:   /* CCB request was invalid */
1110                 return (EINVAL);
1111         case CAM_RESRC_UNAVAIL: /* Resource Unavailable */
1112                 return (ENOMEM);
1113         case CAM_BUSY:          /* CAM subsytem is busy */
1114         case CAM_UA_ABORT:      /* Unable to abort CCB request */
1115                 return (EBUSY);
1116         default:
1117                 return (ENXIO);
1118         }
1119 }
1120
1121 static size_t
1122 targccblen(xpt_opcode func_code)
1123 {
1124         int len;
1125
1126         /* Codes we expect to see as a target */
1127         switch (func_code) {
1128         case XPT_CONT_TARGET_IO:
1129         case XPT_SCSI_IO:
1130                 len = sizeof(struct ccb_scsiio);
1131                 break;
1132         case XPT_ACCEPT_TARGET_IO:
1133                 len = sizeof(struct ccb_accept_tio);
1134                 break;
1135         case XPT_IMMED_NOTIFY:
1136                 len = sizeof(struct ccb_immed_notify);
1137                 break;
1138         case XPT_REL_SIMQ:
1139                 len = sizeof(struct ccb_relsim);
1140                 break;
1141         case XPT_PATH_INQ:
1142                 len = sizeof(struct ccb_pathinq);
1143                 break;
1144         case XPT_DEBUG:
1145                 len = sizeof(struct ccb_debug);
1146                 break;
1147         case XPT_ABORT:
1148                 len = sizeof(struct ccb_abort);
1149                 break;
1150         case XPT_EN_LUN:
1151                 len = sizeof(struct ccb_en_lun);
1152                 break;
1153         default:
1154                 len = sizeof(union ccb);
1155                 break;
1156         }
1157
1158         return (len);
1159 }